KLF4 and ischemia: Of interest, as shown in Fig. 2A–C, in the ischemic penumbra, the co-expression of KLF4-C3 or KLF4-S100A10 increased with time and reached a maximum level at day 7 post-ischemia, whereas the distribution patterns of their expressions were different: where the high levels of KLF4 were expressed, there were relatively low levels of C3 expressed in the ischemic penumbra, and vice versa.